A structure for a connection using connectors or the like is used for a connection of a module substrate that is mounted on a printed board.
Concerning such a connection between substrates, Japanese Laid-Open Patent Publication No. 2001-210977 discloses a mounting structure that is a plug-in mounting structure adapted to insert a PWB (Printed Wiring Board: a plug-in-mounted-type printed wiring board) along a card guide from a front face of a housing and fit the PWB into a back face connector, including: a stopper portion that rotates centering a pin and that applies its own weight to an edge of the PWB to allow the PWB to be automatically locked when the PWB is fitted into the connector without adding any unplugging preventing structure to an ejector portion, to allow the PWB to be released at a touch, and to enable easy designing thereof and; a bracket that is integrated in the stopper portion and that includes a lever unit to operate; a card guide that includes a groove for the stopper portion to escape into when the PWB is inserted or pulled out; and PWB that includes a groove for the stopper portion to fall into simultaneously when its own connector and a connector of a mother board fit each other (Abstract and FIG. 2).
Japanese Laid-Open Patent Publication No. 11-274765 discloses a substrate fixing tool used to attach and detach a printed substrate according to which: the substrate fixing tool includes a base having a flat portion to be fixed to a mother board, and a locking piece provided being movable upward and downward in a receiving hole provided for the base; a daughter board is mounted on the flat portion of the base; the locking piece configured by a member having a substantially U-shaped cross section includes a sliding shaft that is provided in the vicinity of a bended portion of the locking piece and that is slidably supported on the base; a pawl that holds the daughter board sandwiching the daughter board with the flat portion is formed on a free end of the locking piece; and a hooking protrusion that engages with a hooking piece of the base is formed on the other free end of the locking piece (Abstract and FIG. 2).
Concerning a connection between substrates, according to the mounting structure described in Japanese Laid-Open Patent Publication No. 2001-210977, complicated operations are necessary as follows: the bracket attached to the card guide rotates centering the pin; the stopper portion on the tip falls into the groove of the printed board and is locked at the moment of the fitting of the connector when the printed board is inserted; the ejector is pulled up with the stopper being detached from the groove by pulling down the lever of the bracket; and the printed board is pulled out.
According to the substrate fixing tool described in Japanese Laid-Open Patent Publication No. 11-274765, the structure of the substrate fixing tool is complicated as follows: when the rotatable locking piece is pulled down outward, the daughter board is mounted on the mother board and is joined by a connector with the mother board; the locking piece is pulled up and the end of the daughter board is fixed by the pawl; and the other end of the locking piece is a locking releasing lever.
As depicted in FIGS. 1A and 1B, when a plurality of module substrates 4 are mounted on a printed board 2 such as a mother board, connectors 6 and 8 that connect the printed board 2 and the module substrates 4 to each other are disposed between the printed board 2 and the module substrates 4 and, therefore, the connectors 6 and 8 are covered by the module substrates 4 when the module substrates 4 are horizontally mounted to the printed board 2, etc. Therefore, inconvenience has arisen that the connection state of the connectors 6 and 8 is unable to be checked by its appearances. As depicted in FIG. 2, even when the connection state of the connectors 6 and 8 is incomplete, this state is unable to be checked by its appearances.
As depicted in FIG. 3, when vibrations act on an apparatus that is mounted with the printed board 2 or vibrations, etc., are applied to the connectors 6 and 8 that connect the printed board 2 and the module substrate 4 to each other and, thereby, a force F acts on the module substrate 4, the connector 8 may be unplugged from the connector 6. To prevent this unplugging, as depicted in FIG. 4, a locking mechanism 10 to lock the connectors 6 and 8 to each other is necessary between them. In the locking mechanism 10: a pair of fixing bases 12 are installed on the printed board 2 sandwiching the module substrate 4 therebetween; each locking metal fitting 14 installed astride the module substrate 4 is fixed to the fixing base 12 using a fixing screw 16, and, thereby, the connection by each of the connectors 6 and 8 is reinforced. Such installation of the locking parts causes an increase of the cost.
An inserting and pulling mechanism 18 is used for insertion and pulling out of the module substrate 4 into/from the printed board 2 as depicted in FIGS. 5 and 6. FIG. 5 depicts the printed board 2 that includes the inserting and pulling mechanism 18. FIG. 6 is aside view of FIG. 5. In the inserting and pulling mechanism 18, inserting and pulling jig receiving units 20 are installed to the printed board 2 sandwiching the module substrate 4 therebetween, and an inserting and pulling jig 22 is included that is attachable and detachable to/from the inserting and pulling jig receiving unit 20 and that inserts and pulls out the module substrate 4. The inserting and pulling jig 22 includes a lever arm 24 and an L-shaped abutting portion 26 formed therein and also includes a fulcrum portion 28 in a bordering portion between the lever arm 24 and the abutting portion 26. In the vicinity of the fulcrum portion 28, a pin 32 is provided protruding to be inserted into a groove 30 in the inserting and pulling jig receiving unit 20. As depicted in FIGS. 7A, 7B and 7C, the pin 32 is inserted into the groove 30 of the inserting and pulling jig receiving unit 20, thereby, the lever arm 24 is supported by the inserting and pulling jig receiving unit 20, the lever arm 24 is rotated centering the pin 32 of the inserting and pulling jig 22, the abutting portion 26 is pushed against the module substrate 4, and, thereby, the module substrate 4 can be pulled up.
When it is necessary to provide the inserting and pulling mechanism 18 and to insert and pull out the module substrate 4 using the inserting and pulling jig 22 and the locking metal fitting 14 is also installed to the inserting and pulling jig receiving unit 20 (FIG. 9), locking work such as fixation of the locking metal fitting 14 is necessary separately from the connecting work using the connectors. The inserting and pulling mechanisms 18 are provided on both sides of the module substrate 4 and, therefore, an operation using the single inserting and pulling jig 22 causes imbalance and the module substrate 4 may not be attached and detached keeping the module substrate 4 horizontal. Moreover, the connectors 6 and 8 may be broken. Therefore, in the inserting and pulling work using the inserting and pulling jig 22, a worker is forced to execute two types of work using both of his/her hands.
For a positioning mechanism 34 for positioning the printed board 2 and the module substrate 4, a plurality of positioning through holes 36 are formed in the module substrate 4 as depicted in FIG. 8A and a positioning pin 38 is provided for the printed board 2 being protruded therefrom, that penetrates each of the positioning through holes 36 as depicted in FIG. 8B. Therefore, to connect the printed board 2 and the module substrate 4 to each other, the positioning through hole 36 is aligned with the positioning pin 38 of the printed board 2 and the module substrate 4 is superimposed on the printed board 2 and, thereby, the module substrate 4 is positioned at a predetermined position relative to the printed board 2 and, thereby, the fitting of connectors 6 and 8 to each other is executed.
To connect the module substrate 4 to the printed board 2 using the connectors, a plurality of parts are necessary as follows: the locking mechanism 10, the inserting and pulling mechanism 18 and the positioning mechanism 34 are necessary; the inserting and pulling jig 22 is indispensable for the inserting and pulling mechanism 18; etc. Therefore, the cost is increased, and stepwise work is necessary as follows: operations of the mechanism 10, 18 and 34 are necessary; and these operations each need a predetermined sequence; etc. Therefore, the assembling workability is poor.
When the plurality of module substrates 4 are inserted and pulled out, a lever similar to the inserting and pulling jig 22 can be fitted to the module substrate 4. However, the number of parts accordingly increases and the cost is increased.
When the inserting and pulling jig 22 that is usable commonly to various module substrates 4 for insertion and pulling out thereof, the number of parts can be reduced by the number of the inserting and pulling jigs 22 reduced due to the common use and the cost can be reduced. However, the module substrate 4 and the inserting and pulling jig 22 are separated from each other and the degree of freedom for the inserting and pulling jig 22 to move is increased. Therefore, due to a wrong operation, etc. of the inserting and pulling jig 22, the inserting and pulling jig 22 is made into contact with parts on the printing board 2 and parts in the vicinity of an operation area of the inserting and pulling jig 22 may be damaged.
As depicted in FIG. 9, when a plurality of module substrates 401, 402, 403, . . . are mounted on the printed board 2, the plurality of module substrates 401, 402, 403, . . . are disposed adjacent to each other. However, the locking mechanisms 10 and the inserting and pulling mechanisms 18 are installed to each of the module substrates 401, 402, 403, . . . and, therefore, denoting the number of each type of mechanisms installed as “n” and the number of the module substrates 401, 402, 403, . . . as “N”, the number of each type of mechanisms installed n is n=2N and the number of parts of the locking mechanism 10 or the inserting and pulling mechanism 18 is proportional to the number two times as many as the number of module substrates 401, 402, 403, . . . installed. Therefore, this leads to an increase of the cost and, the more the number of parts increases, the poorer the assembling workability becomes.
Japanese Laid-Open Patent Publications Nos. 2001-210977 and 11-274765 do not include any suggestion or any disclosure about the problems concerning the connection between substrates using the connectors as above such as checking of the state of the connection using the connectors is difficult, that the connecting structure is complicated, and that the connection workability is degraded, and also do not disclose any means to solve those problems.